Mutations in nuclear lamins or other proteins of the nuclear envelope are the root cause of a group of phenotypically diverse genetic disorders known as laminopathies, which have symptoms that range from muscular dystrophy to neuropathy to premature aging syndromes. Although precise disease mechanisms remain unclear, there has been substantial progress in our understanding of not only laminopathies, but also the biological roles of nuclear structure. Nuclear envelope dysfunction is associated with altered nuclear activity, impaired structural dynamics, and aberrant cell signaling. Building on these findings, small molecules are being discovered that may become effective therapeutic agents.